Start-ups The Upstarts

Chris Kong has cooked for celebrities such as Guy Savoy, Daniel Humm and, reportedly, Beyonce. But, last year, the 32-year-old quit the glitz and glamour of Michelin-starred kitchens for his own.

They started the popular salad chain in their Georgetown dorm room, and now it's the first unicorn salad start-up valued at $1 billion.

When Pat Brown was working in his lab in 2011, he had "zero" intention of starting a business — much less one that would win U.N. backing and investments from the likes of billionaire Bill Gates.

Sweden is home to one of the world's most robust start-up scenes.

To take a stand against climate change, 25-year-old Barney Swan embarked on a two-month journey, skiing 600 miles across Antarctica on the world's first-ever journey powered solely by renewable energy.

People are obsessed.

Ritesh Agarwal, a Thiel Fellow, is founder and CEO of OYO and one of India's wealthiest self-made entrepreneurs.

CNBC Make It spoke to founders who quit their 9-to-5s and started their own companies to find out.

Plant-based "meat" producer Beyond Meat is backed by investors like Bill Gates and Leonardo DiCaprio.

Allbirds is one of the hottest shoe brands on the market. Co-founder Tim Brown thought of the idea while playing professional soccer in New Zealand.